Key result
PET-derived myocardial steal is linked to ~6.7-fold higher risk of death or MI.
Why the study?
Coronary flow capacity integrates hyperemic myocardial blood flow and coronary flow reserve, but the prognostic value of modified CFC derived from [15O]H2O PET perfusion imaging needed exploration.
Does modified coronary flow capacity derived from [15O]H2O PET perfusion imaging predict the composite of death and nonfatal myocardial infarction in patients with known or suspected coronary artery disease?
Cohort (n=1,300)
Observers blinded to clinical follow-up data
Yes
Does modified coronary flow capacity derived from [15O]H2O PET perfusion imaging predict the composite of death and nonfatal myocardial infarction in patients with known or suspected coronary artery disease?
Modified coronary flow capacity derived from [15O]H2O PET imaging provides independent and incremental prognostic value beyond clinical risk factors and individual perfusion metrics.
BACKGROUND: Coronary flow capacity (CFC) is a measure that integrates hyperemic myocardial blood flow and coronary flow reserve to quantify the pathophysiological impact of coronary artery disease on vasodilator capacity. This study explores the prognostic value of modified CFC derived from [ 15 O]H 2 O positron emission tomography perfusion imaging. METHODS: Quantitative rest/stress perfusion measurements were obtained from 1300 patients with known or suspected coronary artery disease. Patients were classified as having myocardial steal (n=38), severely reduced CFC (n=141), moderately reduced CFC (n=394), minimally reduced CFC (n=245), or normal flow (n=482) using previously defined thresholds. The end point was a composite of death and nonfatal myocardial infarction. RESULTS: During a median follow-up of 5.5 (interquartile range, 3.7–7.8) years, the end point occurred in 153 (12%) patients. Myocardial steal (hazard ratio [HR], 6.70 [95% CI, 3.21–13.99]; P <0.001), severely reduced CFC (HR, 2.35 [95% CI, 1.16–4.78]; P =0.018), and moderately reduced CFC (HR, 1.95 [95% CI, 1.11–3.41]; P =0.020) were associated with worse prognosis compared with normal flow, after adjusting for clinical characteristics. Similarly, in the overall population, increased resting myocardial blood flow (HR, 3.05 [95% CI, 1.68–5.54]; P <0.001), decreased hyperemic myocardial blood flow (HR, 0.68 [95% CI, 0.52–0.90]; P =0.007) and decreased coronary flow reserve (HR, 0.55 [95% CI, 0.42–0.71]; P <0.001) were independently associated with adverse outcome. In a model adjusted for the combined use of perfusion metrics, modified CFC demonstrated independent prognostic value (overall P =0.017). CONCLUSIONS: [ 15 O]H 2 O positron emission tomography–derived resting myocardial blood flow, hyperemic myocardial blood flow, coronary flow reserve, and CFC are prognostic factors for death and nonfatal myocardial infarction in patients with known or suspected coronary artery disease. Importantly, after adjustment for clinical characteristics and the combined use of [ 15 O]H 2 O positron emission tomography perfusion metrics, modified CFC remained independently associated with adverse outcome.
No takes yet. Share an insight, caveat, or question.
Winter et al. (2023) conducted a cohort in Known or suspected coronary artery disease (n=1,300). Myocardial steal (modified coronary flow capacity category) vs. Normal flow was evaluated on Composite of all-cause death and nonfatal myocardial infarction (HR 6.70, 95% CI 3.21-13.99, p=<0.001). In patients with known or suspected coronary artery disease, myocardial steal derived from [15O]H2O PET perfusion imaging was associated with a higher risk of death and nonfatal myocardial infarction (HR 6.70) compared to normal flow.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: